PERMEABILITY OF FLY ASH AND FLY ASH STABILIZED SOILS

Fly ash, a pozzolanic by-product of coal burning power plants, is an abundant potential source of highway and embankment construction material. Some fly ashes are suitable for use as a supplement or replacement for lime and portland cement in soil stabilization applications. The following conclusions are based on the results of a study using a fly ash produced from Wyoming low sulfur coal and two Arkansas soils. (1) Addition of fly ash to clay or sand reduces the permeability. The fly ash was more effective in reducing the permeability of sand (permeability reduced three orders of magnitude at 50% fly ash) than in clay (reduced by a factor of 4 at 50% fly ash). (2) Permeability does not vary greatly with time. (3) Increased compactive effort increases density and reduces permeability in soils. However, reduction in permeability due to increased compactive effort are usually small. (4) The permeability of fly ash, placed in a slurry, varies between 0.0001 cm/sec and 0.000001 cm/sec depending on the amount of water in the slurry. (5) Fly ash placed dry, then saturated, developed shrinkage cracks which created secondary permeability.

  • Record URL:
  • Supplemental Notes:
    • Sponsored in part by Arkansas State Highway Dept., Little Rock.
  • Corporate Authors:

    University of Arkansas, Fayetteville

    Department of Civil Engineering, 4190 Bell Engineering Center
    Fayetteville, AR  United States  72701

    Federal Highway Administration

    Office of Research and Development, 1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    Arkansas State Highway Department

    Division of Planning and Research, P.O. Box 2261
    Little Rock, AR  United States  72203
  • Authors:
    • Parker, D G
    • Thornton, S I
  • Publication Date: 1976-12

Media Info

  • Pagination: 104 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00154044
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: FHWA/RD-M-0356 Final Rpt.
  • Files: NTIS, TRIS, USDOT, STATEDOT
  • Created Date: Jun 17 1977 12:00AM